title: Determination of cyanide in blood by electrospray ionization tandem mass spectrometry after direct injection of dicyanogold.
abstract: An electrospray ionization tandem mass spectrometric (ESI-MS-MS) method has been developed for the determination of cyanide (CN(-)) in blood. Five microliters of blood was hemolyzed with 50 μL of water, then 5 μL of 1 M tetramethylammonium hydroxide solution was added to raise the pH of the hemolysate and to liberate CN(-) from methemoglobin. CN(-) was then reacted with NaAuCl(4) to produce dicyanogold, Au(CN)(2)(-), that was extracted with 75 μL of methyl isobutyl ketone. Ten microliters of the extract was injected directly into an ESI-MS-MS instrument and quantification of CN(-) was performed by selected reaction monitoring of the product ion CN(-) at m/z 26, derived from the precursor ion Au(CN)(2)(-) at m/z 249. CN(-) could be measured in the quantification range of 2.60 to 260 μg/L with the limit of detection at 0.56 μg/L in blood. This method was applied to the analysis of clinical samples and the concentrations of CN(-) in the blood were as follows: 7.13 ± 2.41 μg/L for six healthy non-smokers, 3.08 ± 1.12 μg/L for six CO gas victims, 730 ± 867 μg for 21 house fire victims, and 3,030 ± 97 μg/L for a victim who ingested NaCN. The increase of CN(-) in the blood of a victim who ingested NaN(3) was confirmed using MS-MS for the first time, and the concentrations of CN(-) in the blood, gastric content and urine were 78.5 ± 5.5, 11.8 ± 0.5, and 11.4 ± 0.8 μg/L, respectively.
authors.affiliation: Department of Legal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, 431-3192, Japan. kminakat@hama-med.ac.jp
authors.forename: Kayoko
authors.initials: K
authors.lastname: Minakata
authors.forename: Hideki
authors.initials: H
authors.lastname: Nozawa
authors.forename: Kunio
authors.initials: K
authors.lastname: Gonmori
authors.forename: Itaru
authors.initials: I
authors.lastname: Yamagishi
authors.forename: Masako
authors.initials: M
authors.lastname: Suzuki
authors.forename: Koutaro
authors.initials: K
authors.lastname: Hasegawa
authors.forename: Kanako
authors.initials: K
authors.lastname: Watanabe
authors.forename: Osamu
authors.initials: O
authors.lastname: Suzuki
mesh_terms: D002249:Carbon Monoxide Poisoning / Q000097:blood; D016022:Case-Control Studies; D003486:Cyanides / Q000097:blood*; D017612:Gold Compounds / Q000008:administration & dosage*; D006801:Humans; D057230:Limit of Detection; D015203:Reproducibility of Results; D012907:Smoking / Q000097:blood; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D003486:Cyanides; D017612:Gold Compounds